This dissertation is undertaken under the auspices of both the CSIR, Division of Mining Technology and the University of Natal, School of Mechanical Engineering. The CSIR have outlined two fundamental objectives of the dissertation. Firstly, the need for competent design engineers has become increasingly evident. To this end, an evaluation and research into the science of design methodology has been conducted and regarded as a significant component of the thesis. The rationale behind this aim is that the subject of design has been practiced for thousands of years, but an understanding of the process is comparably in its infancy. The importance of the steps involved in the mechanical design process can in no uncertain terms be overemphasized as the adherence there to results in designs that are least likely prone to failure as well as the attainment of highly efficient product design time scales. This is vitally important more especially when the drive towards multifunctional multidisciplinary teams is rapidly developing in the global market place. Secondly, the CSIR, having done the appropriate market research, have defined the need for the design of a timber handling system to be implemented in a deep level mining environment. It is the authors expressed intent not to separate the theory from the design at hand but rather to allow this thesis to become, for the reader, forum where a holistic and integrated approach to design can be presented. / Thesis (M.Sc.)-University of Natal, Durban, 2000.

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Abstract   Author: Annika Sjögren Arvidson Title: The reflective leadership role in social service organizations   Supervisor: Anders Giertz Assessor: Jan Petersson     I have studied the leadership role of unit managers in social service organizations and their relationship to the concept of reflective approach. I started from a curiosity about how and if unit managers within social services use the concept reflective approach in their leadership role, and how their organizations look upon this and what the consequences are. If in the long term, this affects the individual receiving assistance. All the interviewed persons come from different places, services and organizations. The study is qualitative, with a number of interviews conducted with unit managers. The results show that the concept of reflective approach is used in different ways, and it does not depend on the type of organization whether or not it is used. It could also make a difference for the individual receiving assistance.

5th IFAC Symposium on Mechatronic Systems, Marriott Boston Cambridge, Cambridge, MA, USA, Sept 13-15, 2010

Western Canada is in a post Canadian Wheat Board single-desk market, in which grain handlers face policy, allocation, and logistical changes to the transportation of grains. This research looks at the rails transportation problem for allocating wheat from Prairie to port position, offering a new allocation system that fits the evolving environment of Western Canada’s grain market. Optimization and analysis of the transport of wheat by railroads is performed using geographic information system software as well as spatial and historical data. The studied transportation problem searches to minimize the costs of time rather than look purely at locational costs or closest proximity to port. Through optimization three major bottlenecks are found to constrain the transportation problem; 1) an allocation preference towards Thunder Bay and Vancouver ports, 2) small capacity train inefficiency, and 3) a mismatched distribution of supply and demand between the Class 1 railway firms. Through analysis of counterfactual policies and a scaled sensitivity analysis of the transportation problem, the grains transport system of railroads is found to be dynamic and time efficient; specifically when utilizing larger train capacities, offering open access to rail, and under times of increased availability of supplies. Even under the current circumstances of reduced grain movement and inefficiencies, there are policies and logistics that can be implemented to offer grain handlers in Western Canada with the transportation needed to fulfill their export demands.

Work environment has been an important part of the Swedish working life for a long time and with the help of the Working Environment Law the work environment is mandatory. The purpose of this study was to gain a deeper insight into how the system of middle managers systematic work environment looks like. The question was: How do six middle managers perceive and deal with systematic work environment? A qualitative study was conducted with six middle managers from a global company. During the analysis, there were three main themes to be recognized (cooperation and support facilitates the work environment, problem with the systematic work and difficulties with staff) and six sub themes. The results showed that respondents felt great support from management and safety representatives, which according to the respondents made ​​their systematic work environment easier. In contrast, respondents indicated that work environment was extensive and because of that the experience was that the work never gets finished. It also emerged in the results that the systematic work environment is about trying to change staff attitudes. The conclusion is that systematic work environment is not an easy task for middle managers. Moreover, it seems that systematic work environment also involve working to change attitudes and behaviors. The study wants to contribute to a greater understanding of how the system of middle managers work with the systematic work environment looks like.

Following contractile activity, fast twitch skeletal muscle exhibits increases in submaximal force known as potentiation. Although there is no consensus on the purpose of potentiation, it is known to enhance power during rapid dynamic contractions and counteract the early stages of peripheral fatigue. Potentiation is primarily attributed to phosphorylation of the myosin regulatory light chain (RLC) through a calcium-mediated process which results in increased calcium-sensitivity of crossbridge formation. However, there is a growing body of evidence showing that potentiation can be achieved in the absence of RLC phosphorylation, albeit to a lesser degree. A secondary characteristic of the potentiated contraction is an acceleration of relaxation properties, which could be teleologically beneficial to enhance the cycling rate of rapid motions (e.g. running). However, accelerated relaxation is inconsistent with elevations in calcium-sensitivity as this would tend to slow the time course and slow relaxation. Therefore there are multiple mechanisms involved in potentiation, some of which enhance crossbridge formation, and some of which enhance crossbridge detachment. A possible explanation for these events involves contraction-induced changes in the intracellular cytosolic calcium signal that triggers muscle contraction. For example, elevations in submaximal force could be achieved by increasing the amplitude of the calcium signal while enhanced relaxation speed could be achieved by a shorter duration of the calcium signal. Thus the main objective of this thesis was to investigate the contribution of changes in cytosolic Ca²⁺ to force potentiation. To achieve this objective, intact lumbrical muscles were extracted from the hind feet of C57BL/6 mice for use as the experimental model. The first study in this thesis examined cytosolic calcium signals during posttetanic potentiation using high (AM-fura-2 and AM-indo-1) and low (AM-furaptra) affinity calcium-sensitive fluorescent indicators to monitor resting and peak calcium respectively, both before and after a potentiating stimulation protocol of 2.5 s of 20 Hz stimulation at 37^oC. This protocol resulted in an immediate 17±3% increase in twitch force (n=10; P<0.05), though this potentiation dissipated quickly, lasting only 30 s. Resting cytosolic Ca²⁺ was also increased following the potentiating stimulus as indicated by increases of 11.1 ± 1.3% and 8.1 ± 1.3% in the fura-2 and indo-1 fluorescence ratios respectively. Like the force potentiation, these increases were short lived, lasting 20-30 s. No changes were detected in either the amplitude or kinetics of the Ca²⁺ transients following the potentiating stimulus. Western blotting analysis of the myosin heavy chain isoforms which determine the contractile phenotype of lumbrical muscle revealed predominance of fast type IIX fibres, while immunohistochemical analysis of proteins important for relaxation, namely parvalbumin, sarco-endoplasmic reticulum Ca²⁺ ATPase (SERCA) 1a and SERCA2a, revealed that the expression of these proteins in lumbrical moderated those found in the soleus (slow) and EDL (fast) archetypes. Surprisingly, despite the fast phenotype of the lumbrical, it exhibited low expression of the skeletal muscle isoform of myosin light chain kinase, the enzyme responsible for phosphorylating the myosin RLC, and high expression of myosin targeting phosphatase subunit 2, the enzyme responsible for dephosphorylating the myosin RLC. These data were corroborated by a complete lack of myosin RLC phosphorylation in either the rested or potentiated states. It was thus concluded that elevations in resting cytosolic calcium concentration, in the absence of changes in the intracellular calcium transient and RLC phosphorylation, can potentiate twitch force. The next objective of this thesis was to determine if there are changes in the cytosolic calcium transient during staircase potentiation, defined as a stepwise increase in twitch force during low frequency stimulation (<10 Hz). Staircase potentiation has been repeatedly demonstrated to exhibit more robust potentiation than posttetanic potentiation in the absence of RLC phosphorylation. It was hypothesized that while the calcium transient is not altered during posttetanic potentiation, it may be an important potentiating factor in staircase due to the lower rest intervals between successive contractions. The effects of temperature on the intracellular calcium transient during staircase potentiation were also examined as part of this investigation. Here, lumbricals were loaded with AM- furaptra and then subjected to stimulation at 8 Hz for 8.0 s to induce staircase potentiation at either 30 or 37^oC. This stimulation protocol resulted in a 26.8 ± 3.2 % increase in twitch force at 37^oC (P<0.05) and a 6.8 ± 1.9 % decrease in twitch force at 30^oC (P<0.05) at the 8 s mark. Both the peak amplitude and the calcium-time integral of the calcium transient decreased during the first 2.0 s of the protocol (P<0.05), however these decreases were greater at 30^oC than 37^oC (P<0.05 amplitude; P=0.09 area). While peak amplitude remained low throughout the duration of the protocol, the calcium-time integral began to increase after the 2 s time point (P<0.05), a change reflective of the progressive increases in the 50% decay time and full width at half maximum of the calcium transient (P<0.05). Regression analysis of raw furaptra fluorescence ratios revealed a progressive decline in the peak amplitude of the calcium transients throughout the protocol which was not present at 37^oC. The increases in the duration of the calcium transient were mirrored by increases in the half relaxation time of the twitch contractions at both 30 and 37^oC, which had initially been reduced by ~20 and 9 % at 30 and 37^oC during the first 2 s of the protocol. Therefore the degree of staircase potentiation depends, in part, on the magnitude of the decline in the amplitude and the degree of slowing of the cytosolic calcium transient. The declines in calcium transient amplitude noted above occurred simultaneously with increased rates of relaxation and abbreviated contraction times. To determine if there was a causal relationship between the reduced amplitude and the faster contractions, AM-furaptra-loaded lumbrical muscles were stimulated at 8 Hz for 2 s in the presence and absence of caffeine, an agonist of the calcium release channel. Caffeine treatment attenuated the decline of the calcium transient amplitude (P<0.05), and was associated with greater potentiation at 37^oC (P<0.05), and attenuated force loss at 30^oC (P<0.05). Despite the increases in calcium and force, the relaxation times and rates of relaxation exhibited a greater acceleration following caffeine treatment (P<0.05). Therefore the relaxation-enhancing factor during potentiated twitches cannot be attributed to the calcium transient, and must be localized to changes on the myofilament. The case for inorganic phosphate as the effector is made. Similar to the findings of the posttetanic potentiation study, the resting cytosolic calcium concentration was elevated during staircase potentiation, as revealed by fura-2 ratio signals. The largest increase occurring immediately following the first twitch of the protocol. This coincided with the largest increases in force potentiation at both 30 and 37^oC. This finding is in accordance with the initial conclusion that elevations in resting calcium can enhance twitch force and contribute to potentiation, though the mechanism of action is unclear. One possibility is that increases in resting calcium, sub-threshold for force production, can enhance the number of attached but non-force producing crossbridges, thereby accelerating the transition of crossbridges to force-producing states upon calcium-release following stimulation. To test this hypothesis, the resting stiffness, a measure of crossbridge attachment, of lumbrical muscles was examined before and after a potentiating stimulus of 20 Hz 2.5 s. Resting stiffness was assessed using sinusoidal length oscillations, ~0.5 nm per half sarcomere in amplitude and ranging in frequency from 10-200 Hz. Subsequent analysis revealed decreases in the elastic stiffness (P<0.05) that lasted for ~20 s which were greater in magnitude (P<0.05) than increases in viscous stiffness which only lasted for ~5 s. This finding is consistent with the disappearance of short range elastic component (SREC) upon stretch or muscle activation which is commonly attributed to a population of stable, bound crossbridges in resting muscle. Subsequent analysis using imposed length changes to eliminate the SREC prior to contraction had no effect on the amplitude or duration of a subsequent twitch or tetanic contraction, and the changes in elastic and viscous stiffness of resting muscle were identical whether SREC was ablated by a contraction or imposed length change. Therefore it appears that potentiation occurs without an associated increase in bound crossbridges at rest, and may actually occur with fewer bound crossbridges at rest than the unpotentiated state. The lack of effect may be related to the relaxation-enhancing factor discussed above, and be an important feature of skeletal muscle serving to protect against damage via an involuntary eccentric contraction. This thesis describes potentiation as a complex and important biological function which is the sum of factors that serve to enhance and oppose force production.

Background: The automotive industry accounts for a large part of the European economic structure. Due to both economical and environmental impacts, the industry has undergone substantial changes and companies have to increase their efficiency to stay competitive. An improvement-area, which can be directly influenced by the company is the internal material handling. A new technology that potentially supports the internal material handling process is the radio frequency identification (RFID) technology, which is perceived as a fruitful successor of the common barcoding technology. Even though the RFID technology shows multiple benefits over the barcoding technology, many companies are still reluctant to the application of the new method. The authors therefore strive to provide a deeper understanding of the following two research questions:   RQ 1: To what extent and how is RFID currently applied in the internal material handling process in the investigated automotive companies? RQ 2: For what reasons did the investigated automotive companies decide to apply or not apply RFID technologies to support their internal material handling process?   Purpose: The purpose of this thesis is to show through a multiple case study to what extent and how RFID technology is currently applied to support the internal material handling process in a number of companies in the automotive sector, both original equipment manufacturers (OEMs) and suppliers. Thereupon the main reasons for or against the application of RFID in these companies are examined.   Method: This thesis adopts a positivistic perspective and a deductive approach. It is designed as a qualitative multiple case study carried out in four different companies with five different plants in the automotive industry. Empirical data was gathered through interviews. The analysis is based on primary as well as secondary data.   Conclusions: Throughout the course of the study it became apparent that the RFID technology is on the radar of all investigated companies. Only Scania Zwolle, Volvo Skövde and Bosch Homburg apply the technology and see concrete benefits in the usage of RFID above barcoding. The extent of application here differs from a large scale to a small scale. The three companies name benefits such as an improved automatic tracking &amp; tracing system with improved real-time data quality and a reduction in costs, which is mainly achieved through a reduction of manual labour. Additionally they face benefits, which are business-specific such as the possibility for automatic alerts throughout the internal material handling process at Scania Zwolle, the need for a ‘silent’ successor over barcoding at Volvo Skövde and a supporting tool for their lean management program at Bosch Homburg. VDL Nedcar Born and Scania Oskarshamn in turn name concrete reasons for not applying the technology. VDL Nedcar Born is undergoing substantial changes in their production facility which currently has priority and Scania Oskarshamn does not see benefits that outweigh the high costs for the RFID technology.

Det är inte ovanligt förekommande att ambulanspersonal råkar ut för hot och våldshändelser och enligt statistiken är detta ett problem som ökar hela tiden. Enligt Arbetsmiljöverket står vård och omsorgssektorn för 60 % av samtliga anmälningar inom hot och våldskategorin. Syftet med denna studie var att beskriva ambulanssjuksköterskans upplevelser och hantering kring hot och våld i det dagliga arbetet. Metod: Studien genomfördes som en kvalitativ intervjustudie där fem intervjuer med ambulanssjuksköterskor genomfördes. Ur resultatet framkom ett generellt tema; utsatt för hot och våld, med fem tillhörande kategorier; otrygg miljö, säkerhetstänkande, förebyggande strategier, avledande strategier och känslomässig hantering. Vidare påvisade resultatet att hot och våldssituationer inte enbart handlar om verbala hot eller våldshandlingar. Även situationer som upplevdes obehagliga, medförde en känsla av oro eller otrygghet. Det framkom ett antal olika situationer som kunde resultera i hot eller våld och som upplevdes som påfrestande för ambulanspersonalen. Vidare visade det sig att hanteringen för dessa situationer var många och personalen var nöjda med de handlingsplaner som fanns att tillgå, det var också vanligt att ambulanspersonalen själva utarbetade en beredskapsplan utifrån det givna tillfället där hot och våld kunde tänkas förekomma för att kunna hantera en eventuell våldsam situation. Vikten av att ha förebyggande strategier lyftes upp och betonades som särskilt viktig. Känslorna efter att ha blivit utsatt för hot eller våld kom ofta i efterhand och därav ansågs det viktigt med tid för eftertanke och reflektion. / It is not an uncommon occurrence that paramedics encounter threats and incidents of violence. According to statistics, this is a problem that is increasing over time. According to Arbetsmiljöverket the healthcare sector stands for 60 % of all notifications in the threats and violence category. The purpose of this study was to describe the ambulance nurse´s experiences of threats and violence in their daily work and how these situations are handled. Method: The study was performed as a qualitative interview study in which five interviews with ambulance nurses was conducted. The outcome of the result revealed a general theme; subjected to threats and violence, with five related categories: unsafe environment, safety awareness, prevention strategies, diversionary strategies, and emotional management. Additionally the results demonstrate that threats and violent situations are not only about verbal threats or acts of violence. Even situations that were experienced unpleasant, resulting in a feeling of anxiety or insecurity. It revealed a number of different situations that could result in threats or violence and this were perceived as stressful for the ambulance crew. Furthermore, strategies to manage these situations were many and the staff were satisfied with the contingency plan that was available, it was also common for paramedics themselves drew up a contingency plan based on the given time where threats and violence could be anticipated for such terms to face a possible violent situation. The importance of preventative work was lifted up and was emphasized as particularly important. Feelings after having been exposed to threats or violence often came afterwards and therefore it was considered important time for thought and reflection.